>
>W3BP was asking about the voltage at the end of an antenna. I've been
>thinking about that too,
>Looking at a center fed 1/2 wave dipole: At 1500Watts, the 50 Ohm feedpoint
>sees 273V at 5.5 Amps if my math is correct. The end of the antenna is a
>very high impedance, and I'm just guessing at 3300 Ohms.
Probably pretty close. Wire diameter is a large factor.
>It could be more.
>Based on end feeding a 1/2 wave we must match 3-5kOhms. The current is
>minimal but the voltage peaks, and it works out that 2-3KV would be present.
>Experience and gut feeling tell me that it must be or at least can be more
>than that. Anyone have the real figures?
I measured the potential at the feedpoint of my 160m Hertz antenna. (1/2
wave end fed against gnd.) With 100v-p input at 50-ohms, the antenna
side of the L-network measured 1100v-p with my HP oscilloscope.
>I doubt that we can take a direct
>measurement.
>
Doubt not.
>Perhaps at the very end the current is zero and the voltage is
>infinite...not probable, but the range of possibility is large. Geo>K0FF
>
>
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>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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